Need some advice on how to properly clean some rock

[Midway]

Hi there, my friend just gave something like 50 pounds of live rock, well not that live anymore cause he had them without water and plus he had a major coral die off on his tank. He no longer has his tank running that's why he gave them to me. The advice that i need is that is it enough to put in boiled water? Or do i need to do somthing else to really clean them cause i dont want to put in my sump if they still some bad stuff.

Thanks,

Manny